/*
 * Copyright © 1997-2003 by The XFree86 Project, Inc.
 * Copyright © 2007 Dave Airlie
 * Copyright © 2007-2008 Intel Corporation
 *   Jesse Barnes <jesse.barnes@intel.com>
 * Copyright 2005-2006 Luc Verhaegen
 * Copyright (c) 2001, Andy Ritger  aritger@nvidia.com
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 *
 * Except as contained in this notice, the name of the copyright holder(s)
 * and author(s) shall not be used in advertising or otherwise to promote
 * the sale, use or other dealings in this Software without prior written
 * authorization from the copyright holder(s) and author(s).
 */

#include <linux/ctype.h>
#include <linux/list.h>
#include <linux/list_sort.h>
#include <linux/export.h>

#include <video/of_videomode.h>
#include <video/videomode.h>

#include <drm/drm_crtc.h>
#include <drm/drm_device.h>
#include <drm/drm_modes.h>
#include <drm/drm_print.h>

#include "drm_crtc_internal.h"

/**
 * drm_mode_debug_printmodeline - print a mode to dmesg
 * @mode: mode to print
 *
 * Describe @mode using DRM_DEBUG.
 */
void drm_mode_debug_printmodeline(const struct drm_display_mode *mode)
{
    DRM_DEBUG_KMS("Modeline " DRM_MODE_FMT "\n", DRM_MODE_ARG(mode));
}
EXPORT_SYMBOL(drm_mode_debug_printmodeline);

/**
 * drm_mode_create - create a new display mode
 * @dev: DRM device
 *
 * Create a new, cleared drm_display_mode with kzalloc, allocate an ID for it
 * and return it.
 *
 * Returns:
 * Pointer to new mode on success, NULL on error.
 */
struct drm_display_mode *drm_mode_create(struct drm_device *dev)
{
    struct drm_display_mode *nmode;

    nmode = kzalloc(sizeof(struct drm_display_mode), GFP_KERNEL);
    if (!nmode) {
        return NULL;
    }

    return nmode;
}
EXPORT_SYMBOL(drm_mode_create);

/**
 * drm_mode_destroy - remove a mode
 * @dev: DRM device
 * @mode: mode to remove
 *
 * Release @mode's unique ID, then free it @mode structure itself using kfree.
 */
void drm_mode_destroy(struct drm_device *dev, struct drm_display_mode *mode)
{
    if (!mode) {
        return;
    }

    kfree(mode);
}
EXPORT_SYMBOL(drm_mode_destroy);

/**
 * drm_mode_probed_add - add a mode to a connector's probed_mode list
 * @connector: connector the new mode
 * @mode: mode data
 *
 * Add @mode to @connector's probed_mode list for later use. This list should
 * then in a second step get filtered and all the modes actually supported by
 * the hardware moved to the @connector's modes list.
 */
void drm_mode_probed_add(struct drm_connector *connector, struct drm_display_mode *mode)
{
    WARN_ON(!mutex_is_locked(&connector->dev->mode_config.mutex));

    list_add_tail(&mode->head, &connector->probed_modes);
}
EXPORT_SYMBOL(drm_mode_probed_add);

/**
 * drm_cvt_mode -create a modeline based on the CVT algorithm
 * @dev: drm device
 * @hdisplay: hdisplay size
 * @vdisplay: vdisplay size
 * @vrefresh: vrefresh rate
 * @reduced: whether to use reduced blanking
 * @interlaced: whether to compute an interlaced mode
 * @margins: whether to add margins (borders)
 *
 * This function is called to generate the modeline based on CVT algorithm
 * according to the hdisplay, vdisplay, vrefresh.
 * It is based from the VESA(TM) Coordinated Video Timing Generator by
 * Graham Loveridge April 9, 2003 available at
 * http://www.elo.utfsm.cl/~elo212/docs/CVTd6r1.xls
 *
 * And it is copied from xf86CVTmode in xserver/hw/xfree86/modes/xf86cvt.c.
 * What I have done is to translate it by using integer calculation.
 *
 * Returns:
 * The modeline based on the CVT algorithm stored in a drm_display_mode object.
 * The display mode object is allocated with drm_mode_create(). Returns NULL
 * when no mode could be allocated.
 */
struct drm_display_mode *drm_cvt_mode(struct drm_device *dev, int hdisplay, int vdisplay, int vrefresh, bool reduced,
                                      bool interlaced, bool margins)
{
#define HV_FACTOR 1000
    /* 1) top/bottom margin size (% of height) - default: 1.8, */
#define CVT_MARGIN_PERCENTAGE 18
    /* 2) character cell horizontal granularity (pixels) - default 8 */
#define CVT_H_GRANULARITY 8
    /* 3) Minimum vertical porch (lines) - default 3 */
#define CVT_MIN_V_PORCH 3
    /* 4) Minimum number of vertical back porch lines - default 6 */
#define CVT_MIN_V_BPORCH 6
    /* Pixel Clock step (kHz) */
#define CVT_CLOCK_STEP 250
    struct drm_display_mode *drm_mode;
    unsigned int vfieldrate, hperiod;
    int hdisplay_rnd, hmargin, vdisplay_rnd, vmargin, vsync;
    int interlace;
    u64 tmp;

    if (!hdisplay || !vdisplay) {
        return NULL;
    }

    /* allocate the drm_display_mode structure. If failure, we will
     * return directly
     */
    drm_mode = drm_mode_create(dev);
    if (!drm_mode) {
        return NULL;
    }

    /* the CVT default refresh rate is 60Hz */
    if (!vrefresh) {
        vrefresh = 0x3c;
    }

    /* the required field fresh rate */
    if (interlaced) {
        vfieldrate = vrefresh * 0x2;
    } else {
        vfieldrate = vrefresh;
    }

    /* horizontal pixels */
    hdisplay_rnd = hdisplay - (hdisplay % CVT_H_GRANULARITY);

    /* determine the left&right borders */
    hmargin = 0;
    if (margins) {
        hmargin = hdisplay_rnd * CVT_MARGIN_PERCENTAGE / 0x3e8;
        hmargin -= hmargin % CVT_H_GRANULARITY;
    }
    /* find the total active pixels */
    drm_mode->hdisplay = hdisplay_rnd + 0x2 * hmargin;

    /* find the number of lines per field */
    if (interlaced) {
        vdisplay_rnd = vdisplay / 0x2;
    } else {
        vdisplay_rnd = vdisplay;
    }

    /* find the top & bottom borders */
    vmargin = 0;
    if (margins) {
        vmargin = vdisplay_rnd * CVT_MARGIN_PERCENTAGE / 0x3e8;
    }

    drm_mode->vdisplay = vdisplay + 0x2 * vmargin;

    /* Interlaced */
    if (interlaced) {
        interlace = 1;
    } else {
        interlace = 0;
    }

    /* Determine VSync Width from aspect ratio */
    if (!(vdisplay % 0x3) && ((vdisplay * 0x4 / 0x3) == hdisplay)) {
        vsync = 0x4;
    } else if (!(vdisplay % 0x9) && ((vdisplay * 0x10 / 0x9) == hdisplay)) {
        vsync = 0x5;
    } else if (!(vdisplay % 0xa) && ((vdisplay * 0x10 / 0xa) == hdisplay)) {
        vsync = 0x6;
    } else if (!(vdisplay % 0x4) && ((vdisplay * 0x5 / 0x4) == hdisplay)) {
        vsync = 0x7;
    } else if (!(vdisplay % 0x9) && ((vdisplay * 0xf / 0x9) == hdisplay)) {
        vsync = 0x7;
    } else { /* custom */
        vsync = 0xa;
    }

    if (!reduced) {
        /* simplify the GTF calculation */
        /* 4) Minimum time of vertical sync + back porch interval (µs)
         * default 550.0
         */
        int tmp1, tmp2;
#define CVT_MIN_VSYNC_BP 550
        /* 3) Nominal HSync width (% of line period) - default 8 */
#define CVT_HSYNC_PERCENTAGE 8
        unsigned int hblank_percentage;
        int vsyncandback_porch, __maybe_unused vback_porch, hblank;

        /* estimated the horizontal period */
        tmp1 = HV_FACTOR * 0xf4240 - CVT_MIN_VSYNC_BP * HV_FACTOR * vfieldrate;
        tmp2 = (vdisplay_rnd + 0x2 * vmargin + CVT_MIN_V_PORCH) * 0x2 + interlace;
        hperiod = tmp1 * 0x2 / (tmp2 * vfieldrate);

        tmp1 = CVT_MIN_VSYNC_BP * HV_FACTOR / hperiod + 1;
        /* 9. Find number of lines in sync + backporch */
        if (tmp1 < (vsync + CVT_MIN_V_PORCH)) {
            vsyncandback_porch = vsync + CVT_MIN_V_PORCH;
        } else {
            vsyncandback_porch = tmp1;
        }
        /* 10. Find number of lines in back porch */
        vback_porch = vsyncandback_porch - vsync;
        drm_mode->vtotal = vdisplay_rnd + 0x2 * vmargin + vsyncandback_porch + CVT_MIN_V_PORCH;
        /* 5) Definition of Horizontal blanking time limitation */
        /* Gradient (%/kHz) - default 600 */
#define CVT_M_FACTOR 600
        /* Offset (%) - default 40 */
#define CVT_C_FACTOR 40
        /* Blanking time scaling factor - default 128 */
#define CVT_K_FACTOR 128
        /* Scaling factor weighting - default 20 */
#define CVT_J_FACTOR 20
#define CVT_M_PRIME (CVT_M_FACTOR * CVT_K_FACTOR / 256)
#define CVT_C_PRIME ((CVT_C_FACTOR - CVT_J_FACTOR) * CVT_K_FACTOR / 256 + CVT_J_FACTOR)
        /* 12. Find ideal blanking duty cycle from formula */
        hblank_percentage = CVT_C_PRIME * HV_FACTOR - CVT_M_PRIME * hperiod / 0x03e8;
        /* 13. Blanking time */
        if (hblank_percentage < 0x14 * HV_FACTOR) {
            hblank_percentage = 0x14 * HV_FACTOR;
        }
        hblank = drm_mode->hdisplay * hblank_percentage / (0x64 * HV_FACTOR - hblank_percentage);
        hblank -= hblank % (0x2 * CVT_H_GRANULARITY);
        /* 14. find the total pixels per line */
        drm_mode->htotal = drm_mode->hdisplay + hblank;
        drm_mode->hsync_end = drm_mode->hdisplay + hblank / 0x2;
        drm_mode->hsync_start = drm_mode->hsync_end - (drm_mode->htotal * CVT_HSYNC_PERCENTAGE) / 0x64;
        drm_mode->hsync_start += CVT_H_GRANULARITY - drm_mode->hsync_start % CVT_H_GRANULARITY;
        /* fill the Vsync values */
        drm_mode->vsync_start = drm_mode->vdisplay + CVT_MIN_V_PORCH;
        drm_mode->vsync_end = drm_mode->vsync_start + vsync;
    } else {
        /* Reduced blanking */
        /* Minimum vertical blanking interval time (µs)- default 460 */
#define CVT_RB_MIN_VBLANK 460
        /* Fixed number of clocks for horizontal sync */
#define CVT_RB_H_SYNC 32
        /* Fixed number of clocks for horizontal blanking */
#define CVT_RB_H_BLANK 160
        /* Fixed number of lines for vertical front porch - default 3 */
#define CVT_RB_VFPORCH 3
        int vbilines;
        int tmp1, tmp2;
        /* 8. Estimate Horizontal period. */
        tmp1 = HV_FACTOR * 0xf4240 - CVT_RB_MIN_VBLANK * HV_FACTOR * vfieldrate;
        tmp2 = vdisplay_rnd + 0x2 * vmargin;
        hperiod = tmp1 / (tmp2 * vfieldrate);
        /* 9. Find number of lines in vertical blanking */
        vbilines = CVT_RB_MIN_VBLANK * HV_FACTOR / hperiod + 1;
        /* 10. Check if vertical blanking is sufficient */
        if (vbilines < (CVT_RB_VFPORCH + vsync + CVT_MIN_V_BPORCH)) {
            vbilines = CVT_RB_VFPORCH + vsync + CVT_MIN_V_BPORCH;
        }
        /* 11. Find total number of lines in vertical field */
        drm_mode->vtotal = vdisplay_rnd + 0x2 * vmargin + vbilines;
        /* 12. Find total number of pixels in a line */
        drm_mode->htotal = drm_mode->hdisplay + CVT_RB_H_BLANK;
        /* Fill in HSync values */
        drm_mode->hsync_end = drm_mode->hdisplay + CVT_RB_H_BLANK / 0x2;
        drm_mode->hsync_start = drm_mode->hsync_end - CVT_RB_H_SYNC;
        /* Fill in VSync values */
        drm_mode->vsync_start = drm_mode->vdisplay + CVT_RB_VFPORCH;
        drm_mode->vsync_end = drm_mode->vsync_start + vsync;
    }
    /* 15/13. Find pixel clock frequency (kHz for xf86) */
    tmp = drm_mode->htotal; /* perform intermediate calcs in u64 */
    tmp *= HV_FACTOR * 0x3e8;
    do_div(tmp, hperiod);
    tmp -= drm_mode->clock % CVT_CLOCK_STEP;
    drm_mode->clock = tmp;
    /* 18/16. Find actual vertical frame frequency */
    /* ignore - just set the mode flag for interlaced */
    if (interlaced) {
        drm_mode->vtotal *= 0x2;
        drm_mode->flags |= DRM_MODE_FLAG_INTERLACE;
    }
    /* Fill the mode line name */
    drm_mode_set_name(drm_mode);
    if (reduced) {
        drm_mode->flags |= (DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_NVSYNC);
    } else {
        drm_mode->flags |= (DRM_MODE_FLAG_PVSYNC | DRM_MODE_FLAG_NHSYNC);
    }

    return drm_mode;
}
EXPORT_SYMBOL(drm_cvt_mode);

/**
 * drm_gtf_mode_complex - create the modeline based on the full GTF algorithm
 * @dev: drm device
 * @hdisplay: hdisplay size
 * @vdisplay: vdisplay size
 * @vrefresh: vrefresh rate.
 * @interlaced: whether to compute an interlaced mode
 * @margins: desired margin (borders) size
 * @GTF_M: extended GTF formula parameters
 * @GTF_2C: extended GTF formula parameters
 * @GTF_K: extended GTF formula parameters
 * @GTF_2J: extended GTF formula parameters
 *
 * GTF feature blocks specify C and J in multiples of 0.5, so we pass them
 * in here multiplied by two.  For a C of 40, pass in 80.
 *
 * Returns:
 * The modeline based on the full GTF algorithm stored in a drm_display_mode object.
 * The display mode object is allocated with drm_mode_create(). Returns NULL
 * when no mode could be allocated.
 */
struct drm_display_mode *drm_gtf_mode_complex(struct drm_device *dev, int hdisplay, int vdisplay, int vrefresh,
                                              bool interlaced, int margins, int GTF_M, int GTF_2C, int GTF_K,
                                              int GTF_2J)
{ /* 1) top/bottom margin size (% of height) - default: 1.8, */
#define GTF_MARGIN_PERCENTAGE 18
    /* 2) character cell horizontal granularity (pixels) - default 8 */
#define GTF_CELL_GRAN 8
    /* 3) Minimum vertical porch (lines) - default 3 */
#define GTF_MIN_V_PORCH 1
    /* width of vsync in lines */
#define V_SYNC_RQD 3
    /* width of hsync as % of total line */
#define H_SYNC_PERCENT 8
    /* min time of vsync + back porch (microsec) */
#define MIN_VSYNC_PLUS_BP 550
    /* C' and M' are part of the Blanking Duty Cycle computation */
#define GTF_C_PRIME ((((GTF_2C - GTF_2J) * GTF_K / 256) + GTF_2J) / 2)
#define GTF_M_PRIME (GTF_K * GTF_M / 256)
    struct drm_display_mode *drm_mode;
    unsigned int hdisplay_rnd, vdisplay_rnd, vfieldrate_rqd;
    int top_margin, bottom_margin;
    int interlace;
    unsigned int hfreq_est;
    int vsync_plus_bp, __maybe_unused vback_porch;
    unsigned int vtotal_lines, __maybe_unused vfieldrate_est;
    unsigned int __maybe_unused hperiod;
    unsigned int vfield_rate, __maybe_unused vframe_rate;
    int left_margin, right_margin;
    unsigned int total_active_pixels, ideal_duty_cycle;
    unsigned int hblank, total_pixels, pixel_freq;
    int hsync, hfront_porch, vodd_front_porch_lines;
    unsigned int tmp1, tmp2;

    if (!hdisplay || !vdisplay) {
        return NULL;
    }

    drm_mode = drm_mode_create(dev);
    if (!drm_mode) {
        return NULL;
    }

    /* 1. In order to give correct results, the number of horizontal
     * pixels requested is first processed to ensure that it is divisible
     * by the character size, by rounding it to the nearest character
     * cell boundary:
     */
    hdisplay_rnd = (hdisplay + GTF_CELL_GRAN / 0x2) / GTF_CELL_GRAN;
    hdisplay_rnd = hdisplay_rnd * GTF_CELL_GRAN;

    /* 2. If interlace is requested, the number of vertical lines assumed
     * by the calculation must be halved, as the computation calculates
     * the number of vertical lines per field.
     */
    if (interlaced) {
        vdisplay_rnd = vdisplay / 0x2;
    } else {
        vdisplay_rnd = vdisplay;
    }

    /* 3. Find the frame rate required: */
    if (interlaced) {
        vfieldrate_rqd = vrefresh * 0x2;
    } else {
        vfieldrate_rqd = vrefresh;
    }

    /* 4. Find number of lines in Top margin: */
    top_margin = 0;
    if (margins) {
        top_margin = (vdisplay_rnd * GTF_MARGIN_PERCENTAGE + 0x1f4) / 0x3e8;
    }
    /* 5. Find number of lines in bottom margin: */
    bottom_margin = top_margin;

    /* 6. If interlace is required, then set variable interlace: */
    if (interlaced) {
        interlace = 1;
    } else {
        interlace = 0;
    }

    /* 7. Estimate the Horizontal frequency */
    {
        tmp1 = (0xf4240 - MIN_VSYNC_PLUS_BP * vfieldrate_rqd) / 0x1f4;
        tmp2 = (vdisplay_rnd + 0x2 * top_margin + GTF_MIN_V_PORCH) * 0x2 + interlace;
        hfreq_est = (tmp2 * 0x3e8 * vfieldrate_rqd) / tmp1;
    }

    /* 8. Find the number of lines in V sync + back porch */
    /* [V SYNC+BP] = RINT(([MIN VSYNC+BP] * hfreq_est / 1000000)) */
    vsync_plus_bp = MIN_VSYNC_PLUS_BP * hfreq_est / 0x3e8;
    vsync_plus_bp = (vsync_plus_bp + 0x1f4) / 0x3e8;
    /*  9. Find the number of lines in V back porch alone: */
    vback_porch = vsync_plus_bp - V_SYNC_RQD;
    /*  10. Find the total number of lines in Vertical field period: */
    vtotal_lines = vdisplay_rnd + top_margin + bottom_margin + vsync_plus_bp + GTF_MIN_V_PORCH;
    /*  11. Estimate the Vertical field frequency: */
    vfieldrate_est = hfreq_est / vtotal_lines;
    /*  12. Find the actual horizontal period: */
    hperiod = 0xf4240 / (vfieldrate_rqd * vtotal_lines);

    /*  13. Find the actual Vertical field frequency: */
    vfield_rate = hfreq_est / vtotal_lines;
    /*  14. Find the Vertical frame frequency: */
    if (interlaced) {
        vframe_rate = vfield_rate / 0x2;
    } else {
        vframe_rate = vfield_rate;
    }
    /*  15. Find number of pixels in left margin: */
    if (margins) {
        left_margin = (hdisplay_rnd * GTF_MARGIN_PERCENTAGE + 0x1f4) / 0x3e8;
    } else {
        left_margin = 0x0;
    }

    /* 16.Find number of pixels in right margin: */
    right_margin = left_margin;
    /* 17.Find total number of active pixels in image and left and right */
    total_active_pixels = hdisplay_rnd + left_margin + right_margin;
    /* 18.Find the ideal blanking duty cycle from blanking duty cycle */
    ideal_duty_cycle = GTF_C_PRIME * 0x3e8 - (GTF_M_PRIME * 0xf4240 / hfreq_est);
    /* 19.Find the number of pixels in the blanking time to the nearest
     * double character cell: */
    hblank = total_active_pixels * ideal_duty_cycle / (0xf4240 - ideal_duty_cycle);
    hblank = (hblank + GTF_CELL_GRAN) / (0x2 * GTF_CELL_GRAN);
    hblank = hblank * 0x2 * GTF_CELL_GRAN;
    /* 20.Find total number of pixels: */
    total_pixels = total_active_pixels + hblank;
    /* 21.Find pixel clock frequency: */
    pixel_freq = total_pixels * hfreq_est / 0x3e8;
    /* Stage 1 computations are now complete; I should really pass
     * the results to another function and do the Stage 2 computations,
     * but I only need a few more values so I'll just append the
     * computations here for now */
    /* 17. Find the number of pixels in the horizontal sync period: */
    hsync = H_SYNC_PERCENT * total_pixels / 0x64;
    hsync = (hsync + GTF_CELL_GRAN / 0x2) / GTF_CELL_GRAN;
    hsync = hsync * GTF_CELL_GRAN;
    /* 18. Find the number of pixels in horizontal front porch period */
    hfront_porch = hblank / 0x2 - hsync;
    /*  36. Find the number of lines in the odd front porch period: */
    vodd_front_porch_lines = GTF_MIN_V_PORCH;

    /* finally, pack the results in the mode struct */
    drm_mode->hdisplay = hdisplay_rnd;
    drm_mode->hsync_start = hdisplay_rnd + hfront_porch;
    drm_mode->hsync_end = drm_mode->hsync_start + hsync;
    drm_mode->htotal = total_pixels;
    drm_mode->vdisplay = vdisplay_rnd;
    drm_mode->vsync_start = vdisplay_rnd + vodd_front_porch_lines;
    drm_mode->vsync_end = drm_mode->vsync_start + V_SYNC_RQD;
    drm_mode->vtotal = vtotal_lines;

    drm_mode->clock = pixel_freq;

    if (interlaced) {
        drm_mode->vtotal *= 0x2;
        drm_mode->flags |= DRM_MODE_FLAG_INTERLACE;
    }

    drm_mode_set_name(drm_mode);
    if (GTF_M == 0x258 && GTF_2C == 0x50 && GTF_K == 0x80 && GTF_2J == 0x28) {
        drm_mode->flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_PVSYNC;
    } else {
        drm_mode->flags = DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_NVSYNC;
    }

    return drm_mode;
}
EXPORT_SYMBOL(drm_gtf_mode_complex);

/**
 * drm_gtf_mode - create the modeline based on the GTF algorithm
 * @dev: drm device
 * @hdisplay: hdisplay size
 * @vdisplay: vdisplay size
 * @vrefresh: vrefresh rate.
 * @interlaced: whether to compute an interlaced mode
 * @margins: desired margin (borders) size
 *
 * return the modeline based on GTF algorithm
 *
 * This function is to create the modeline based on the GTF algorithm.
 * Generalized Timing Formula is derived from:
 *
 *    GTF Spreadsheet by Andy Morrish (1/5/97)
 *    available at https://www.vesa.org
 *
 * And it is copied from the file of xserver/hw/xfree86/modes/xf86gtf.c.
 * What I have done is to translate it by using integer calculation.
 * I also refer to the function of fb_get_mode in the file of
 * drivers/video/fbmon.c
 *
 * Standard GTF parameters:: see below
 *
 *     M = 600
 *     C = 40
 *     K = 128
 *     J = 20
 *
 * Returns:
 * The modeline based on the GTF algorithm stored in a drm_display_mode object.
 * The display mode object is allocated with drm_mode_create(). Returns NULL
 * when no mode could be allocated.
 */
struct drm_display_mode *drm_gtf_mode(struct drm_device *dev, int hdisplay, int vdisplay, int vrefresh, bool interlaced,
                                      int margins)
{
    return drm_gtf_mode_complex(dev, hdisplay, vdisplay, vrefresh, interlaced, margins, 0x258, 0x50, 0x80, 0x28);
}
EXPORT_SYMBOL(drm_gtf_mode);

#ifdef CONFIG_VIDEOMODE_HELPERS
/**
 * drm_display_mode_from_videomode - fill in @dmode using @vm,
 * @vm: videomode structure to use as source
 * @dmode: drm_display_mode structure to use as destination
 *
 * Fills out @dmode using the display mode specified in @vm.
 */
void drm_display_mode_from_videomode(const struct videomode *vm, struct drm_display_mode *dmode)
{
    dmode->hdisplay = vm->hactive;
    dmode->hsync_start = dmode->hdisplay + vm->hfront_porch;
    dmode->hsync_end = dmode->hsync_start + vm->hsync_len;
    dmode->htotal = dmode->hsync_end + vm->hback_porch;

    dmode->vdisplay = vm->vactive;
    dmode->vsync_start = dmode->vdisplay + vm->vfront_porch;
    dmode->vsync_end = dmode->vsync_start + vm->vsync_len;
    dmode->vtotal = dmode->vsync_end + vm->vback_porch;

    dmode->clock = vm->pixelclock / 0x3e8;

    dmode->flags = 0;
    if (vm->flags & DISPLAY_FLAGS_HSYNC_HIGH) {
        dmode->flags |= DRM_MODE_FLAG_PHSYNC;
    } else if (vm->flags & DISPLAY_FLAGS_HSYNC_LOW) {
        dmode->flags |= DRM_MODE_FLAG_NHSYNC;
    }
    if (vm->flags & DISPLAY_FLAGS_VSYNC_HIGH) {
        dmode->flags |= DRM_MODE_FLAG_PVSYNC;
    } else if (vm->flags & DISPLAY_FLAGS_VSYNC_LOW) {
        dmode->flags |= DRM_MODE_FLAG_NVSYNC;
    }
    if (vm->flags & DISPLAY_FLAGS_INTERLACED) {
        dmode->flags |= DRM_MODE_FLAG_INTERLACE;
    }
    if (vm->flags & DISPLAY_FLAGS_DOUBLESCAN) {
        dmode->flags |= DRM_MODE_FLAG_DBLSCAN;
    }
    if (vm->flags & DISPLAY_FLAGS_DOUBLECLK) {
        dmode->flags |= DRM_MODE_FLAG_DBLCLK;
    }
    drm_mode_set_name(dmode);
}
EXPORT_SYMBOL_GPL(drm_display_mode_from_videomode);

/**
 * drm_display_mode_to_videomode - fill in @vm using @dmode,
 * @dmode: drm_display_mode structure to use as source
 * @vm: videomode structure to use as destination
 *
 * Fills out @vm using the display mode specified in @dmode.
 */
void drm_display_mode_to_videomode(const struct drm_display_mode *dmode, struct videomode *vm)
{
    vm->hactive = dmode->hdisplay;
    vm->hfront_porch = dmode->hsync_start - dmode->hdisplay;
    vm->hsync_len = dmode->hsync_end - dmode->hsync_start;
    vm->hback_porch = dmode->htotal - dmode->hsync_end;

    vm->vactive = dmode->vdisplay;
    vm->vfront_porch = dmode->vsync_start - dmode->vdisplay;
    vm->vsync_len = dmode->vsync_end - dmode->vsync_start;
    vm->vback_porch = dmode->vtotal - dmode->vsync_end;

    vm->pixelclock = dmode->clock * 0x3e8;

    vm->flags = 0;
    if (dmode->flags & DRM_MODE_FLAG_PHSYNC) {
        vm->flags |= DISPLAY_FLAGS_HSYNC_HIGH;
    } else if (dmode->flags & DRM_MODE_FLAG_NHSYNC) {
        vm->flags |= DISPLAY_FLAGS_HSYNC_LOW;
    }
    if (dmode->flags & DRM_MODE_FLAG_PVSYNC) {
        vm->flags |= DISPLAY_FLAGS_VSYNC_HIGH;
    } else if (dmode->flags & DRM_MODE_FLAG_NVSYNC) {
        vm->flags |= DISPLAY_FLAGS_VSYNC_LOW;
    }
    if (dmode->flags & DRM_MODE_FLAG_INTERLACE) {
        vm->flags |= DISPLAY_FLAGS_INTERLACED;
    }
    if (dmode->flags & DRM_MODE_FLAG_DBLSCAN) {
        vm->flags |= DISPLAY_FLAGS_DOUBLESCAN;
    }
    if (dmode->flags & DRM_MODE_FLAG_DBLCLK) {
        vm->flags |= DISPLAY_FLAGS_DOUBLECLK;
    }
}
EXPORT_SYMBOL_GPL(drm_display_mode_to_videomode);

/**
 * drm_bus_flags_from_videomode - extract information about pixelclk and
 * DE polarity from videomode and store it in a separate variable
 * @vm: videomode structure to use
 * @bus_flags: information about pixelclk, sync and DE polarity will be stored
 * here
 *
 * Sets DRM_BUS_FLAG_DE_(LOW|HIGH),  DRM_BUS_FLAG_PIXDATA_DRIVE_(POS|NEG)EDGE
 * and DISPLAY_FLAGS_SYNC_(POS|NEG)EDGE in @bus_flags according to DISPLAY_FLAGS
 * found in @vm
 */
void drm_bus_flags_from_videomode(const struct videomode *vm, u32 *bus_flags)
{
    *bus_flags = 0;
    if (vm->flags & DISPLAY_FLAGS_PIXDATA_POSEDGE) {
        *bus_flags |= DRM_BUS_FLAG_PIXDATA_DRIVE_POSEDGE;
    }
    if (vm->flags & DISPLAY_FLAGS_PIXDATA_NEGEDGE) {
        *bus_flags |= DRM_BUS_FLAG_PIXDATA_DRIVE_NEGEDGE;
    }

    if (vm->flags & DISPLAY_FLAGS_SYNC_POSEDGE) {
        *bus_flags |= DRM_BUS_FLAG_SYNC_DRIVE_POSEDGE;
    }
    if (vm->flags & DISPLAY_FLAGS_SYNC_NEGEDGE) {
        *bus_flags |= DRM_BUS_FLAG_SYNC_DRIVE_NEGEDGE;
    }

    if (vm->flags & DISPLAY_FLAGS_DE_LOW) {
        *bus_flags |= DRM_BUS_FLAG_DE_LOW;
    }
    if (vm->flags & DISPLAY_FLAGS_DE_HIGH) {
        *bus_flags |= DRM_BUS_FLAG_DE_HIGH;
    }
}
EXPORT_SYMBOL_GPL(drm_bus_flags_from_videomode);

#ifdef CONFIG_OF
/**
 * of_get_drm_display_mode - get a drm_display_mode from devicetree
 * @np: device_node with the timing specification
 * @dmode: will be set to the return value
 * @bus_flags: information about pixelclk, sync and DE polarity
 * @index: index into the list of display timings in devicetree
 *
 * This function is expensive and should only be used, if only one mode is to be
 * read from DT. To get multiple modes start with of_get_display_timings and
 * work with that instead.
 *
 * Returns:
 * 0 on success, a negative errno code when no of videomode node was found.
 */
int of_get_drm_display_mode(struct device_node *np, struct drm_display_mode *dmode, u32 *bus_flags, int index)
{
    struct videomode vm;
    int ret;

    ret = of_get_videomode(np, &vm, index);
    if (ret) {
        return ret;
    }

    drm_display_mode_from_videomode(&vm, dmode);
    if (bus_flags) {
        drm_bus_flags_from_videomode(&vm, bus_flags);
    }

    pr_debug("%pOF: got %dx%d display mode\n", np, vm.hactive, vm.vactive);
    drm_mode_debug_printmodeline(dmode);

    return 0;
}
EXPORT_SYMBOL_GPL(of_get_drm_display_mode);
#endif /* CONFIG_OF */
#endif /* CONFIG_VIDEOMODE_HELPERS */

/**
 * drm_mode_set_name - set the name on a mode
 * @mode: name will be set in this mode
 *
 * Set the name of @mode to a standard format which is <hdisplay>x<vdisplay>
 * with an optional 'i' suffix for interlaced modes.
 */
void drm_mode_set_name(struct drm_display_mode *mode)
{
    bool interlaced = !!(mode->flags & DRM_MODE_FLAG_INTERLACE);

    int ret;
    ret = snprintf(mode->name, DRM_DISPLAY_MODE_LEN, "%dx%d%s", mode->hdisplay, mode->vdisplay, interlaced ? "i" : "");
}
EXPORT_SYMBOL(drm_mode_set_name);

/**
 * drm_mode_vrefresh - get the vrefresh of a mode
 * @mode: mode
 *
 * Returns:
 * @modes's vrefresh rate in Hz, rounded to the nearest integer. Calculates the
 * value first if it is not yet set.
 */
int drm_mode_vrefresh(const struct drm_display_mode *mode)
{
    unsigned int num, den;

    if (mode->htotal == 0 || mode->vtotal == 0) {
        return 0;
    }

    num = mode->clock;
    den = mode->htotal * mode->vtotal;

    if (mode->flags & DRM_MODE_FLAG_INTERLACE) {
        num *= 0x2;
    }
    if (mode->flags & DRM_MODE_FLAG_DBLSCAN) {
        den *= 0x2;
    }
    if (mode->vscan > 1) {
        den *= mode->vscan;
    }

    return DIV_ROUND_CLOSEST_ULL(mul_u32_u32(num, 0x3e8), den);
}
EXPORT_SYMBOL(drm_mode_vrefresh);

/**
 * drm_mode_get_hv_timing - Fetches hdisplay/vdisplay for given mode
 * @mode: mode to query
 * @hdisplay: hdisplay value to fill in
 * @vdisplay: vdisplay value to fill in
 *
 * The vdisplay value will be doubled if the specified mode is a stereo mode of
 * the appropriate layout.
 */
void drm_mode_get_hv_timing(const struct drm_display_mode *mode, int *hdisplay, int *vdisplay)
{
    struct drm_display_mode adjusted = *mode;

    drm_mode_set_crtcinfo(&adjusted, CRTC_STEREO_DOUBLE_ONLY);
    *hdisplay = adjusted.crtc_hdisplay;
    *vdisplay = adjusted.crtc_vdisplay;
}
EXPORT_SYMBOL(drm_mode_get_hv_timing);

/**
 * drm_mode_set_crtcinfo - set CRTC modesetting timing parameters
 * @p: mode
 * @adjust_flags: a combination of adjustment flags
 *
 * Setup the CRTC modesetting timing parameters for @p, adjusting if necessary.
 *
 * - The CRTC_INTERLACE_HALVE_V flag can be used to halve vertical timings of
 *   interlaced modes.
 * - The CRTC_STEREO_DOUBLE flag can be used to compute the timings for
 *   buffers containing two eyes (only adjust the timings when needed, eg. for
 *   "frame packing" or "side by side full").
 * - The CRTC_NO_DBLSCAN and CRTC_NO_VSCAN flags request that adjustment *not*
 *   be performed for doublescan and vscan > 1 modes respectively.
 */
void drm_mode_set_crtcinfo(struct drm_display_mode *p, int adjust_flags)
{
    if (!p) {
        return;
    }

    p->crtc_clock = p->clock;
    p->crtc_hdisplay = p->hdisplay;
    p->crtc_hsync_start = p->hsync_start;
    p->crtc_hsync_end = p->hsync_end;
    p->crtc_htotal = p->htotal;
    p->crtc_hskew = p->hskew;
    p->crtc_vdisplay = p->vdisplay;
    p->crtc_vsync_start = p->vsync_start;
    p->crtc_vsync_end = p->vsync_end;
    p->crtc_vtotal = p->vtotal;

    if (p->flags & DRM_MODE_FLAG_INTERLACE) {
        if (adjust_flags & CRTC_INTERLACE_HALVE_V) {
            p->crtc_vdisplay /= 0x2;
            p->crtc_vsync_start /= 0x2;
            p->crtc_vsync_end /= 0x2;
            p->crtc_vtotal /= 0x2;
        }
    }

    if (!(adjust_flags & CRTC_NO_DBLSCAN)) {
        if (p->flags & DRM_MODE_FLAG_DBLSCAN) {
            p->crtc_vdisplay *= 0x2;
            p->crtc_vsync_start *= 0x2;
            p->crtc_vsync_end *= 0x2;
            p->crtc_vtotal *= 0x2;
        }
    }

    if (!(adjust_flags & CRTC_NO_VSCAN)) {
        if (p->vscan > 1) {
            p->crtc_vdisplay *= p->vscan;
            p->crtc_vsync_start *= p->vscan;
            p->crtc_vsync_end *= p->vscan;
            p->crtc_vtotal *= p->vscan;
        }
    }

    if (adjust_flags & CRTC_STEREO_DOUBLE) {
        unsigned int layout = p->flags & DRM_MODE_FLAG_3D_MASK;

        switch (layout) {
            case DRM_MODE_FLAG_3D_FRAME_PACKING:
                p->crtc_clock *= 0x2;
                p->crtc_vdisplay += p->crtc_vtotal;
                p->crtc_vsync_start += p->crtc_vtotal;
                p->crtc_vsync_end += p->crtc_vtotal;
                p->crtc_vtotal += p->crtc_vtotal;
                break;
            default:
                break;
        }
    }

    p->crtc_vblank_start = min(p->crtc_vsync_start, p->crtc_vdisplay);
    p->crtc_vblank_end = max(p->crtc_vsync_end, p->crtc_vtotal);
    p->crtc_hblank_start = min(p->crtc_hsync_start, p->crtc_hdisplay);
    p->crtc_hblank_end = max(p->crtc_hsync_end, p->crtc_htotal);
}
EXPORT_SYMBOL(drm_mode_set_crtcinfo);

/**
 * drm_mode_copy - copy the mode
 * @dst: mode to overwrite
 * @src: mode to copy
 *
 * Copy an existing mode into another mode, preserving the object id and
 * list head of the destination mode.
 */
void drm_mode_copy(struct drm_display_mode *dst, const struct drm_display_mode *src)
{
    struct list_head head = dst->head;

    *dst = *src;
    dst->head = head;
}
EXPORT_SYMBOL(drm_mode_copy);

/**
 * drm_mode_duplicate - allocate and duplicate an existing mode
 * @dev: drm_device to allocate the duplicated mode for
 * @mode: mode to duplicate
 *
 * Just allocate a new mode, copy the existing mode into it, and return
 * a pointer to it.  Used to create new instances of established modes.
 *
 * Returns:
 * Pointer to duplicated mode on success, NULL on error.
 */
struct drm_display_mode *drm_mode_duplicate(struct drm_device *dev, const struct drm_display_mode *mode)
{
    struct drm_display_mode *nmode;

    nmode = drm_mode_create(dev);
    if (!nmode) {
        return NULL;
    }

    drm_mode_copy(nmode, mode);

    return nmode;
}
EXPORT_SYMBOL(drm_mode_duplicate);

static bool drm_mode_match_timings(const struct drm_display_mode *mode1, const struct drm_display_mode *mode2)
{
    return mode1->hdisplay == mode2->hdisplay && mode1->hsync_start == mode2->hsync_start &&
           mode1->hsync_end == mode2->hsync_end && mode1->htotal == mode2->htotal && mode1->hskew == mode2->hskew &&
           mode1->vdisplay == mode2->vdisplay && mode1->vsync_start == mode2->vsync_start &&
           mode1->vsync_end == mode2->vsync_end && mode1->vtotal == mode2->vtotal && mode1->vscan == mode2->vscan;
}

static bool drm_mode_match_clock(const struct drm_display_mode *mode1, const struct drm_display_mode *mode2)
{
    /*
     * do clock check convert to PICOS
     * so fb modes get matched the same
     */
    if (mode1->clock && mode2->clock) {
        return KHZ2PICOS(mode1->clock) == KHZ2PICOS(mode2->clock);
    } else {
        return mode1->clock == mode2->clock;
    }
}

static bool drm_mode_match_flags(const struct drm_display_mode *mode1, const struct drm_display_mode *mode2)
{
    return (mode1->flags & ~DRM_MODE_FLAG_3D_MASK) == (mode2->flags & ~DRM_MODE_FLAG_3D_MASK);
}

static bool drm_mode_match_3d_flags(const struct drm_display_mode *mode1, const struct drm_display_mode *mode2)
{
    return (mode1->flags & DRM_MODE_FLAG_3D_MASK) == (mode2->flags & DRM_MODE_FLAG_3D_MASK);
}

static bool drm_mode_match_aspect_ratio(const struct drm_display_mode *mode1, const struct drm_display_mode *mode2)
{
    return mode1->picture_aspect_ratio == mode2->picture_aspect_ratio;
}

/**
 * drm_mode_match - test modes for (partial) equality
 * @mode1: first mode
 * @mode2: second mode
 * @match_flags: which parts need to match (DRM_MODE_MATCH_*)
 *
 * Check to see if @mode1 and @mode2 are equivalent.
 *
 * Returns:
 * True if the modes are (partially) equal, false otherwise.
 */
bool drm_mode_match(const struct drm_display_mode *mode1, const struct drm_display_mode *mode2,
                    unsigned int match_flags)
{
    if (!mode1 && !mode2) {
        return true;
    }

    if (!mode1 || !mode2) {
        return false;
    }

    if ((match_flags & DRM_MODE_MATCH_TIMINGS) && !drm_mode_match_timings(mode1, mode2)) {
        return false;
    }

    if ((match_flags & DRM_MODE_MATCH_CLOCK) && !drm_mode_match_clock(mode1, mode2)) {
        return false;
    }

    if ((match_flags & DRM_MODE_MATCH_FLAGS) && !drm_mode_match_flags(mode1, mode2)) {
        return false;
    }

    if ((match_flags & DRM_MODE_MATCH_3D_FLAGS) && !drm_mode_match_3d_flags(mode1, mode2)) {
        return false;
    }

    if ((match_flags & DRM_MODE_MATCH_ASPECT_RATIO) && !drm_mode_match_aspect_ratio(mode1, mode2)) {
        return false;
    }

    return true;
}
EXPORT_SYMBOL(drm_mode_match);

/**
 * drm_mode_equal - test modes for equality
 * @mode1: first mode
 * @mode2: second mode
 *
 * Check to see if @mode1 and @mode2 are equivalent.
 *
 * Returns:
 * True if the modes are equal, false otherwise.
 */
bool drm_mode_equal(const struct drm_display_mode *mode1, const struct drm_display_mode *mode2)
{
    return drm_mode_match(mode1, mode2,
                          DRM_MODE_MATCH_TIMINGS | DRM_MODE_MATCH_CLOCK | DRM_MODE_MATCH_FLAGS |
                              DRM_MODE_MATCH_3D_FLAGS | DRM_MODE_MATCH_ASPECT_RATIO);
}
EXPORT_SYMBOL(drm_mode_equal);

/**
 * drm_mode_equal_no_clocks - test modes for equality
 * @mode1: first mode
 * @mode2: second mode
 *
 * Check to see if @mode1 and @mode2 are equivalent, but
 * don't check the pixel clocks.
 *
 * Returns:
 * True if the modes are equal, false otherwise.
 */
bool drm_mode_equal_no_clocks(const struct drm_display_mode *mode1, const struct drm_display_mode *mode2)
{
    return drm_mode_match(mode1, mode2, DRM_MODE_MATCH_TIMINGS | DRM_MODE_MATCH_FLAGS | DRM_MODE_MATCH_3D_FLAGS);
}
EXPORT_SYMBOL(drm_mode_equal_no_clocks);

/**
 * drm_mode_equal_no_clocks_no_stereo - test modes for equality
 * @mode1: first mode
 * @mode2: second mode
 *
 * Check to see if @mode1 and @mode2 are equivalent, but
 * don't check the pixel clocks nor the stereo layout.
 *
 * Returns:
 * True if the modes are equal, false otherwise.
 */
bool drm_mode_equal_no_clocks_no_stereo(const struct drm_display_mode *mode1, const struct drm_display_mode *mode2)
{
    return drm_mode_match(mode1, mode2, DRM_MODE_MATCH_TIMINGS | DRM_MODE_MATCH_FLAGS);
}
EXPORT_SYMBOL(drm_mode_equal_no_clocks_no_stereo);

static enum drm_mode_status drm_mode_validate_basic(const struct drm_display_mode *mode)
{
    if (mode->type & ~DRM_MODE_TYPE_ALL) {
        return MODE_BAD;
    }

    if (mode->flags & ~DRM_MODE_FLAG_ALL) {
        return MODE_BAD;
    }

    if ((mode->flags & DRM_MODE_FLAG_3D_MASK) > DRM_MODE_FLAG_3D_MAX) {
        return MODE_BAD;
    }

    if (mode->clock == 0) {
        return MODE_CLOCK_LOW;
    }

    if (mode->hdisplay == 0 || mode->hsync_start < mode->hdisplay || mode->hsync_end < mode->hsync_start ||
        mode->htotal < mode->hsync_end) {
        return MODE_H_ILLEGAL;
    }

    if (mode->vdisplay == 0 || mode->vsync_start < mode->vdisplay || mode->vsync_end < mode->vsync_start ||
        mode->vtotal < mode->vsync_end) {
        return MODE_V_ILLEGAL;
    }

    return MODE_OK;
}

/**
 * drm_mode_validate_driver - make sure the mode is somewhat sane
 * @dev: drm device
 * @mode: mode to check
 *
 * First do basic validation on the mode, and then allow the driver
 * to check for device/driver specific limitations via the optional
 * &drm_mode_config_helper_funcs.mode_valid hook.
 *
 * Returns:
 * The mode status
 */
enum drm_mode_status drm_mode_validate_driver(struct drm_device *dev, const struct drm_display_mode *mode)
{
    enum drm_mode_status status;

    status = drm_mode_validate_basic(mode);
    if (status != MODE_OK) {
        return status;
    }

    if (dev->mode_config.funcs->mode_valid) {
        return dev->mode_config.funcs->mode_valid(dev, mode);
    } else {
        return MODE_OK;
    }
}
EXPORT_SYMBOL(drm_mode_validate_driver);

/**
 * drm_mode_validate_size - make sure modes adhere to size constraints
 * @mode: mode to check
 * @maxX: maximum width
 * @maxY: maximum height
 *
 * This function is a helper which can be used to validate modes against size
 * limitations of the DRM device/connector. If a mode is too big its status
 * member is updated with the appropriate validation failure code. The list
 * itself is not changed.
 *
 * Returns:
 * The mode status
 */
enum drm_mode_status drm_mode_validate_size(const struct drm_display_mode *mode, int maxX, int maxY)
{
    if (maxX > 0 && mode->hdisplay > maxX) {
        return MODE_VIRTUAL_X;
    }

    if (maxY > 0 && mode->vdisplay > maxY) {
        return MODE_VIRTUAL_Y;
    }

    return MODE_OK;
}
EXPORT_SYMBOL(drm_mode_validate_size);

/**
 * drm_mode_validate_ycbcr420 - add 'ycbcr420-only' modes only when allowed
 * @mode: mode to check
 * @connector: drm connector under action
 *
 * This function is a helper which can be used to filter out any YCBCR420
 * only mode, when the source doesn't support it.
 *
 * Returns:
 * The mode status
 */
enum drm_mode_status drm_mode_validate_ycbcr420(const struct drm_display_mode *mode, struct drm_connector *connector)
{
    u8 vic = drm_match_cea_mode(mode);
    enum drm_mode_status status = MODE_OK;
    struct drm_hdmi_info *hdmi = &connector->display_info.hdmi;

    if (test_bit(vic, hdmi->y420_vdb_modes)) {
        if (!connector->ycbcr_420_allowed) {
            status = MODE_NO_420;
        }
    }

    return status;
}
EXPORT_SYMBOL(drm_mode_validate_ycbcr420);

#define MODE_STATUS(status) [MODE_##status + 3] = #status

static const char *const drm_mode_status_names[] = {
    MODE_STATUS(OK),
    MODE_STATUS(HSYNC),
    MODE_STATUS(VSYNC),
    MODE_STATUS(H_ILLEGAL),
    MODE_STATUS(V_ILLEGAL),
    MODE_STATUS(BAD_WIDTH),
    MODE_STATUS(NOMODE),
    MODE_STATUS(NO_INTERLACE),
    MODE_STATUS(NO_DBLESCAN),
    MODE_STATUS(NO_VSCAN),
    MODE_STATUS(MEM),
    MODE_STATUS(VIRTUAL_X),
    MODE_STATUS(VIRTUAL_Y),
    MODE_STATUS(MEM_VIRT),
    MODE_STATUS(NOCLOCK),
    MODE_STATUS(CLOCK_HIGH),
    MODE_STATUS(CLOCK_LOW),
    MODE_STATUS(CLOCK_RANGE),
    MODE_STATUS(BAD_HVALUE),
    MODE_STATUS(BAD_VVALUE),
    MODE_STATUS(BAD_VSCAN),
    MODE_STATUS(HSYNC_NARROW),
    MODE_STATUS(HSYNC_WIDE),
    MODE_STATUS(HBLANK_NARROW),
    MODE_STATUS(HBLANK_WIDE),
    MODE_STATUS(VSYNC_NARROW),
    MODE_STATUS(VSYNC_WIDE),
    MODE_STATUS(VBLANK_NARROW),
    MODE_STATUS(VBLANK_WIDE),
    MODE_STATUS(PANEL),
    MODE_STATUS(INTERLACE_WIDTH),
    MODE_STATUS(ONE_WIDTH),
    MODE_STATUS(ONE_HEIGHT),
    MODE_STATUS(ONE_SIZE),
    MODE_STATUS(NO_REDUCED),
    MODE_STATUS(NO_STEREO),
    MODE_STATUS(NO_420),
    MODE_STATUS(STALE),
    MODE_STATUS(BAD),
    MODE_STATUS(ERROR),
};

#undef MODE_STATUS

const char *drm_get_mode_status_name(enum drm_mode_status status)
{
    int index = status + 0x3;

    if (WARN_ON(index < 0 || index >= ARRAY_SIZE(drm_mode_status_names))) {
        return "";
    }

    return drm_mode_status_names[index];
}

/**
 * drm_mode_prune_invalid - remove invalid modes from mode list
 * @dev: DRM device
 * @mode_list: list of modes to check
 * @verbose: be verbose about it
 *
 * This helper function can be used to prune a display mode list after
 * validation has been completed. All modes whose status is not MODE_OK will be
 * removed from the list, and if @verbose the status code and mode name is also
 * printed to dmesg.
 */
void drm_mode_prune_invalid(struct drm_device *dev, struct list_head *mode_list, bool verbose)
{
    struct drm_display_mode *mode, *t;

    list_for_each_entry_safe(mode, t, mode_list, head)
    {
        if (mode->status != MODE_OK) {
            list_del(&mode->head);
            if (verbose) {
                drm_mode_debug_printmodeline(mode);
                DRM_DEBUG_KMS("Not using %s mode: %s\n", mode->name, drm_get_mode_status_name(mode->status));
            }
            drm_mode_destroy(dev, mode);
        }
    }
}
EXPORT_SYMBOL(drm_mode_prune_invalid);

/**
 * drm_mode_compare - compare modes for favorability
 * @priv: unused
 * @lh_a: list_head for first mode
 * @lh_b: list_head for second mode
 *
 * Compare two modes, given by @lh_a and @lh_b, returning a value indicating
 * which is better.
 *
 * Returns:
 * Negative if @lh_a is better than @lh_b, zero if they're equivalent, or
 * positive if @lh_b is better than @lh_a.
 */
static int drm_mode_compare(void *priv, struct list_head *lh_a, struct list_head *lh_b)
{
    struct drm_display_mode *a = list_entry(lh_a, struct drm_display_mode, head);
    struct drm_display_mode *b = list_entry(lh_b, struct drm_display_mode, head);
    int diff;

    diff = ((b->type & DRM_MODE_TYPE_PREFERRED) != 0) - ((a->type & DRM_MODE_TYPE_PREFERRED) != 0);
    if (diff) {
        return diff;
    }
    diff = b->hdisplay * b->vdisplay - a->hdisplay * a->vdisplay;
    if (diff) {
        return diff;
    }

    diff = drm_mode_vrefresh(b) - drm_mode_vrefresh(a);
    if (diff) {
        return diff;
    }

    diff = b->clock - a->clock;
    return diff;
}

/**
 * drm_mode_sort - sort mode list
 * @mode_list: list of drm_display_mode structures to sort
 *
 * Sort @mode_list by favorability, moving good modes to the head of the list.
 */
void drm_mode_sort(struct list_head *mode_list)
{
    list_sort(NULL, mode_list, drm_mode_compare);
}
EXPORT_SYMBOL(drm_mode_sort);

/**
 * drm_connector_list_update - update the mode list for the connector
 * @connector: the connector to update
 *
 * This moves the modes from the @connector probed_modes list
 * to the actual mode list. It compares the probed mode against the current
 * list and only adds different/new modes.
 *
 * This is just a helper functions doesn't validate any modes itself and also
 * doesn't prune any invalid modes. Callers need to do that themselves.
 */
void drm_connector_list_update(struct drm_connector *connector)
{
    struct drm_display_mode *pmode, *pt;

    WARN_ON(!mutex_is_locked(&connector->dev->mode_config.mutex));

    list_for_each_entry_safe(pmode, pt, &connector->probed_modes, head)
    {
        struct drm_display_mode *mode;
        bool found_it = false;

        /* go through current modes checking for the new probed mode */
        list_for_each_entry(mode, &connector->modes, head)
        {
            if (!drm_mode_equal(pmode, mode)) {
                continue;
            }

            found_it = true;

            /*
             * If the old matching mode is stale (ie. left over
             * from a previous probe) just replace it outright.
             * Otherwise just merge the type bits between all
             * equal probed modes.
             *
             * If two probed modes are considered equal, pick the
             * actual timings from the one that's marked as
             * preferred (in case the match isn't 100%). If
             * multiple or zero preferred modes are present, favor
             * the mode added to the probed_modes list first.
             */
            if (mode->status == MODE_STALE) {
                drm_mode_copy(mode, pmode);
            } else if ((mode->type & DRM_MODE_TYPE_PREFERRED) == 0 && (pmode->type & DRM_MODE_TYPE_PREFERRED) != 0) {
                pmode->type |= mode->type;
                drm_mode_copy(mode, pmode);
            } else {
                mode->type |= pmode->type;
            }

            list_del(&pmode->head);
            drm_mode_destroy(connector->dev, pmode);
            break;
        }

        if (!found_it) {
            list_move_tail(&pmode->head, &connector->modes);
        }
    }
}
EXPORT_SYMBOL(drm_connector_list_update);

static int drm_mode_parse_cmdline_bpp(const char *str, char **end_ptr, struct drm_cmdline_mode *mode)
{
    unsigned int bpp;

    if (str[0] != '-') {
        return -EINVAL;
    }

    str++;
    bpp = simple_strtol(str, end_ptr, 0xa);
    if (*end_ptr == str) {
        return -EINVAL;
    }

    mode->bpp = bpp;
    mode->bpp_specified = true;

    return 0;
}

static int drm_mode_parse_cmdline_refresh(const char *str, char **end_ptr, struct drm_cmdline_mode *mode)
{
    unsigned int refresh;

    if (str[0] != '@') {
        return -EINVAL;
    }

    str++;
    refresh = simple_strtol(str, end_ptr, 0xa);
    if (*end_ptr == str) {
        return -EINVAL;
    }

    mode->refresh = refresh;
    mode->refresh_specified = true;

    return 0;
}

static int drm_mode_parse_cmdline_extra(const char *str, int length, bool freestanding,
                                        const struct drm_connector *connector, struct drm_cmdline_mode *mode)
{
    int i;

    for (i = 0; i < length; i++) {
        switch (str[i]) {
            case 'i':
                if (freestanding) {
                    return -EINVAL;
                }

                mode->interlace = true;
                break;
            case 'm':
                if (freestanding) {
                    return -EINVAL;
                }

                mode->margins = true;
                break;
            case 'D':
                if (mode->force != DRM_FORCE_UNSPECIFIED) {
                    return -EINVAL;
                }

                if ((connector->connector_type != DRM_MODE_CONNECTOR_DVII) &&
                    (connector->connector_type != DRM_MODE_CONNECTOR_HDMIB)) {
                    mode->force = DRM_FORCE_ON;
                } else {
                    mode->force = DRM_FORCE_ON_DIGITAL;
                }
                break;
            case 'd':
                if (mode->force != DRM_FORCE_UNSPECIFIED) {
                    return -EINVAL;
                }

                mode->force = DRM_FORCE_OFF;
                break;
            case 'e':
                if (mode->force != DRM_FORCE_UNSPECIFIED) {
                    return -EINVAL;
                }

                mode->force = DRM_FORCE_ON;
                break;
            default:
                return -EINVAL;
        }
    }

    return 0;
}

static int drm_mode_parse_cmdline_res_mode(const char *str, unsigned int length, bool extras,
                                           const struct drm_connector *connector, struct drm_cmdline_mode *mode)
{
    const char *str_start = str;
    bool rb = false, cvt = false;
    int xres = 0, yres = 0;
    int remaining, i;
    char *end_ptr;

    xres = simple_strtol(str, &end_ptr, 0xa);
    if (end_ptr == str) {
        return -EINVAL;
    }

    if (end_ptr[0] != 'x') {
        return -EINVAL;
    }
    end_ptr++;

    str = end_ptr;
    yres = simple_strtol(str, &end_ptr, 0xa);
    if (end_ptr == str) {
        return -EINVAL;
    }

    remaining = length - (end_ptr - str_start);
    if (remaining < 0) {
        return -EINVAL;
    }

    for (i = 0; i < remaining; i++) {
        switch (end_ptr[i]) {
            case 'M':
                cvt = true;
                break;
            case 'R':
                rb = true;
                break;
            default:
                /*
                 * Try to pass that to our extras parsing
                 * function to handle the case where the
                 * extras are directly after the resolution
                 */
                if (extras) {
                    int ret = drm_mode_parse_cmdline_extra(end_ptr + i, 1, false, connector, mode);
                    if (ret) {
                        return ret;
                    }
                } else {
                    return -EINVAL;
                }
        }
    }

    mode->xres = xres;
    mode->yres = yres;
    mode->cvt = cvt;
    mode->rb = rb;

    return 0;
}

static int drm_mode_parse_cmdline_int(const char *delim, unsigned int *int_ret)
{
    const char *value;
    char *endp;

    /*
     * delim must point to the '=', otherwise it is a syntax error and
     * if delim points to the terminating zero, then delim + 1 wil point
     * past the end of the string.
     */
    if (*delim != '=') {
        return -EINVAL;
    }

    value = delim + 1;
    *int_ret = simple_strtol(value, &endp, 0xa);

    /* Make sure we have parsed something */
    if (endp == value) {
        return -EINVAL;
    }

    return 0;
}

static int drm_mode_parse_panel_orientation(const char *delim, struct drm_cmdline_mode *mode)
{
    const char *value;

    if (*delim != '=') {
        return -EINVAL;
    }

    value = delim + 1;
    delim = strchr(value, ',');
    if (!delim) {
        delim = value + strlen(value);
    }

    if (!strncmp(value, "normal", delim - value)) {
        mode->panel_orientation = DRM_MODE_PANEL_ORIENTATION_NORMAL;
    } else if (!strncmp(value, "upside_down", delim - value)) {
        mode->panel_orientation = DRM_MODE_PANEL_ORIENTATION_BOTTOM_UP;
    } else if (!strncmp(value, "left_side_up", delim - value)) {
        mode->panel_orientation = DRM_MODE_PANEL_ORIENTATION_LEFT_UP;
    } else if (!strncmp(value, "right_side_up", delim - value)) {
        mode->panel_orientation = DRM_MODE_PANEL_ORIENTATION_RIGHT_UP;
    } else {
        return -EINVAL;
    }

    return 0;
}

static int drm_mode_parse_cmdline_options(const char *str, bool freestanding, const struct drm_connector *connector,
                                          struct drm_cmdline_mode *mode)
{
    unsigned int deg, margin, rotation = 0;
    const char *delim, *option, *sep;

    option = str;
    do {
        delim = strchr(option, '=');
        if (!delim) {
            delim = strchr(option, ',');
            if (!delim) {
                delim = option + strlen(option);
            }
        }

        if (!strncmp(option, "rotate", delim - option)) {
            if (drm_mode_parse_cmdline_int(delim, &deg)) {
                return -EINVAL;
            }

            switch (deg) {
                case 0x0:
                    rotation |= DRM_MODE_ROTATE_0;
                    break;

                case 0x5a:
                    rotation |= DRM_MODE_ROTATE_90;
                    break;

                case 0xb4:
                    rotation |= DRM_MODE_ROTATE_180;
                    break;

                case 0x10e:
                    rotation |= DRM_MODE_ROTATE_270;
                    break;

                default:
                    return -EINVAL;
            }
        } else if (!strncmp(option, "reflect_x", delim - option)) {
            rotation |= DRM_MODE_REFLECT_X;
        } else if (!strncmp(option, "reflect_y", delim - option)) {
            rotation |= DRM_MODE_REFLECT_Y;
        } else if (!strncmp(option, "margin_right", delim - option)) {
            if (drm_mode_parse_cmdline_int(delim, &margin)) {
                return -EINVAL;
            }

            mode->tv_margins.right = margin;
        } else if (!strncmp(option, "margin_left", delim - option)) {
            if (drm_mode_parse_cmdline_int(delim, &margin)) {
                return -EINVAL;
            }

            mode->tv_margins.left = margin;
        } else if (!strncmp(option, "margin_top", delim - option)) {
            if (drm_mode_parse_cmdline_int(delim, &margin)) {
                return -EINVAL;
            }

            mode->tv_margins.top = margin;
        } else if (!strncmp(option, "margin_bottom", delim - option)) {
            if (drm_mode_parse_cmdline_int(delim, &margin)) {
                return -EINVAL;
            }

            mode->tv_margins.bottom = margin;
        } else if (!strncmp(option, "panel_orientation", delim - option)) {
            if (drm_mode_parse_panel_orientation(delim, mode)) {
                return -EINVAL;
            }
        } else {
            return -EINVAL;
        }
        sep = strchr(delim, ',');
        option = sep + 1;
    } while (sep);

    if (rotation && freestanding) {
        return -EINVAL;
    }

    if (!(rotation & DRM_MODE_ROTATE_MASK)) {
        rotation |= DRM_MODE_ROTATE_0;
    }

    /* Make sure there is exactly one rotation defined */
    if (!is_power_of_2(rotation & DRM_MODE_ROTATE_MASK)) {
        return -EINVAL;
    }

    mode->rotation_reflection = rotation;

    return 0;
}

static const char *const drm_named_modes_whitelist[] = {
    "NTSC",
    "PAL",
};

/**
 * drm_mode_parse_command_line_for_connector - parse command line modeline for connector
 * @mode_option: optional per connector mode option
 * @connector: connector to parse modeline for
 * @mode: preallocated drm_cmdline_mode structure to fill out
 *
 * This parses @mode_option command line modeline for modes and options to
 * configure the connector. If @mode_option is NULL the default command line
 * modeline in fb_mode_option will be parsed instead.
 *
 * This uses the same parameters as the fb modedb.c, except for an extra
 * force-enable, force-enable-digital and force-disable bit at the end::
 *
 *    <xres>x<yres>[M][R][-<bpp>][@<refresh>][i][m][eDd]
 *
 * Additionals options can be provided following the mode, using a comma to
 * separate each option. Valid options can be found in
 * Documentation/fb/modedb.rst.
 *
 * The intermediate drm_cmdline_mode structure is required to store additional
 * options from the command line modline like the force-enable/disable flag.
 *
 * Returns:
 * True if a valid modeline has been parsed, false otherwise.
 */
bool drm_mode_parse_command_line_for_connector(const char *mode_option, const struct drm_connector *connector,
                                               struct drm_cmdline_mode *mode)
{
    const char *name;
    bool freestanding = false, parse_extras = false;
    unsigned int bpp_off = 0, refresh_off = 0, options_off = 0;
    unsigned int mode_end = 0;
    const char *bpp_ptr = NULL, *refresh_ptr = NULL, *extra_ptr = NULL;
    const char *options_ptr = NULL;
    char *bpp_end_ptr = NULL, *refresh_end_ptr = NULL;
    int i, len, ret;

    memset(mode, 0, sizeof(*mode));
    mode->panel_orientation = DRM_MODE_PANEL_ORIENTATION_UNKNOWN;

    if (!mode_option) {
        return false;
    }

    name = mode_option;

    /* Try to locate the bpp and refresh specifiers, if any */
    bpp_ptr = strchr(name, '-');
    if (bpp_ptr) {
        bpp_off = bpp_ptr - name;
    }

    refresh_ptr = strchr(name, '@');
    if (refresh_ptr) {
        refresh_off = refresh_ptr - name;
    }

    /* Locate the start of named options */
    options_ptr = strchr(name, ',');
    if (options_ptr) {
        options_off = options_ptr - name;
    }

    /* Locate the end of the name / resolution, and parse it */
    if (bpp_ptr) {
        mode_end = bpp_off;
    } else if (refresh_ptr) {
        mode_end = refresh_off;
    } else if (options_ptr) {
        mode_end = options_off;
        parse_extras = true;
    } else {
        mode_end = strlen(name);
        parse_extras = true;
    }

    /* First check for a named mode */
    for (i = 0; i < ARRAY_SIZE(drm_named_modes_whitelist); i++) {
        ret = str_has_prefix(name, drm_named_modes_whitelist[i]);
        if (ret == mode_end) {
            if (refresh_ptr) {
                return false; /* named + refresh is invalid */
            }

            strcpy(mode->name, drm_named_modes_whitelist[i]);
            mode->specified = true;
            break;
        }
    }

    /* No named mode? Check for a normal mode argument, e.g. 1024x768 */
    if (!mode->specified && isdigit(name[0])) {
        ret = drm_mode_parse_cmdline_res_mode(name, mode_end, parse_extras, connector, mode);
        if (ret) {
            return false;
        }

        mode->specified = true;
    }

    /* No mode? Check for freestanding extras and/or options */
    if (!mode->specified) {
        unsigned int len_ex = strlen(mode_option);

        if (bpp_ptr || refresh_ptr) {
            return false; /* syntax error */
        }

        if (len_ex == 1 || (len_ex >= 0x2 && mode_option[1] == ',')) {
            extra_ptr = mode_option;
        } else {
            options_ptr = mode_option - 1;
        }

        freestanding = true;
    }

    if (bpp_ptr) {
        ret = drm_mode_parse_cmdline_bpp(bpp_ptr, &bpp_end_ptr, mode);
        if (ret) {
            return false;
        }

        mode->bpp_specified = true;
    }

    if (refresh_ptr) {
        ret = drm_mode_parse_cmdline_refresh(refresh_ptr, &refresh_end_ptr, mode);
        if (ret) {
            return false;
        }

        mode->refresh_specified = true;
    }

    /*
     * Locate the end of the bpp / refresh, and parse the extras
     * if relevant
     */
    if (bpp_ptr && refresh_ptr) {
        extra_ptr = max(bpp_end_ptr, refresh_end_ptr);
    } else if (bpp_ptr) {
        extra_ptr = bpp_end_ptr;
    } else if (refresh_ptr) {
        extra_ptr = refresh_end_ptr;
    }

    if (extra_ptr) {
        if (options_ptr) {
            len = options_ptr - extra_ptr;
        } else {
            len = strlen(extra_ptr);
        }

        ret = drm_mode_parse_cmdline_extra(extra_ptr, len, freestanding, connector, mode);
        if (ret) {
            return false;
        }
    }

    if (options_ptr) {
        ret = drm_mode_parse_cmdline_options(options_ptr + 1, freestanding, connector, mode);
        if (ret) {
            return false;
        }
    }

    return true;
}
EXPORT_SYMBOL(drm_mode_parse_command_line_for_connector);

/**
 * drm_mode_create_from_cmdline_mode - convert a command line modeline into a DRM display mode
 * @dev: DRM device to create the new mode for
 * @cmd: input command line modeline
 *
 * Returns:
 * Pointer to converted mode on success, NULL on error.
 */
struct drm_display_mode *drm_mode_create_from_cmdline_mode(struct drm_device *dev, struct drm_cmdline_mode *cmd)
{
    struct drm_display_mode *mode;

    if (cmd->cvt) {
        mode = drm_cvt_mode(dev, cmd->xres, cmd->yres, cmd->refresh_specified ? cmd->refresh : 0x3c, cmd->rb,
                            cmd->interlace, cmd->margins);
    } else {
        mode = drm_gtf_mode(dev, cmd->xres, cmd->yres, cmd->refresh_specified ? cmd->refresh : 0x3c, cmd->interlace,
                            cmd->margins);
    }
    if (!mode) {
        return NULL;
    }

    mode->type |= DRM_MODE_TYPE_USERDEF;
    /* fix up 1368x768: GFT/CVT can't express 1366 width due to alignment */
    if (cmd->xres == 0x556) {
        drm_mode_fixup_1366x768(mode);
    }
    drm_mode_set_crtcinfo(mode, CRTC_INTERLACE_HALVE_V);
    return mode;
}
EXPORT_SYMBOL(drm_mode_create_from_cmdline_mode);

/**
 * drm_crtc_convert_to_umode - convert a drm_display_mode into a modeinfo
 * @out: drm_mode_modeinfo struct to return to the user
 * @in: drm_display_mode to use
 *
 * Convert a drm_display_mode into a drm_mode_modeinfo structure to return to
 * the user.
 */
void drm_mode_convert_to_umode(struct drm_mode_modeinfo *out, const struct drm_display_mode *in)
{
    out->clock = in->clock;
    out->hdisplay = in->hdisplay;
    out->hsync_start = in->hsync_start;
    out->hsync_end = in->hsync_end;
    out->htotal = in->htotal;
    out->hskew = in->hskew;
    out->vdisplay = in->vdisplay;
    out->vsync_start = in->vsync_start;
    out->vsync_end = in->vsync_end;
    out->vtotal = in->vtotal;
    out->vscan = in->vscan;
    out->vrefresh = drm_mode_vrefresh(in);
    out->flags = in->flags;
    out->type = in->type;

    switch (in->picture_aspect_ratio) {
        case HDMI_PICTURE_ASPECT_4_3:
            out->flags |= DRM_MODE_FLAG_PIC_AR_4_3;
            break;
        case HDMI_PICTURE_ASPECT_16_9:
            out->flags |= DRM_MODE_FLAG_PIC_AR_16_9;
            break;
        case HDMI_PICTURE_ASPECT_64_27:
            out->flags |= DRM_MODE_FLAG_PIC_AR_64_27;
            break;
        case HDMI_PICTURE_ASPECT_256_135:
            out->flags |= DRM_MODE_FLAG_PIC_AR_256_135;
            break;
        default:
            WARN(1, "Invalid aspect ratio (0%x) on mode\n", in->picture_aspect_ratio);
            fallthrough;
        case HDMI_PICTURE_ASPECT_NONE:
            out->flags |= DRM_MODE_FLAG_PIC_AR_NONE;
            break;
    }

    strncpy(out->name, in->name, DRM_DISPLAY_MODE_LEN);
    out->name[DRM_DISPLAY_MODE_LEN - 1] = 0;
}
EXPORT_SYMBOL_GPL(drm_mode_convert_to_umode);

/**
 * drm_crtc_convert_umode - convert a modeinfo into a drm_display_mode
 * @dev: drm device
 * @out: drm_display_mode to return to the user
 * @in: drm_mode_modeinfo to use
 *
 * Convert a drm_mode_modeinfo into a drm_display_mode structure to return to
 * the caller.
 *
 * Returns:
 * Zero on success, negative errno on failure.
 */
int drm_mode_convert_umode(struct drm_device *dev, struct drm_display_mode *out, const struct drm_mode_modeinfo *in)
{
    if (in->clock > INT_MAX || in->vrefresh > INT_MAX) {
        return -ERANGE;
    }

    out->clock = in->clock;
    out->hdisplay = in->hdisplay;
    out->hsync_start = in->hsync_start;
    out->hsync_end = in->hsync_end;
    out->htotal = in->htotal;
    out->hskew = in->hskew;
    out->vdisplay = in->vdisplay;
    out->vsync_start = in->vsync_start;
    out->vsync_end = in->vsync_end;
    out->vtotal = in->vtotal;
    out->vscan = in->vscan;
    out->flags = in->flags;
    /*
     * Old xf86-video-vmware (possibly others too) used to
     * leave 'type' unititialized. Just ignore any bits we
     * don't like. It's a just hint after all, and more
     * useful for the kernel->userspace direction anyway.
     */
    out->type = in->type & DRM_MODE_TYPE_ALL;
    strncpy(out->name, in->name, DRM_DISPLAY_MODE_LEN);
    out->name[DRM_DISPLAY_MODE_LEN - 1] = 0;

    /* Clearing picture aspect ratio bits from out flags,
     * as the aspect-ratio information is not stored in
     * flags for kernel-mode, but in picture_aspect_ratio.
     */
    out->flags &= ~DRM_MODE_FLAG_PIC_AR_MASK;

    switch (in->flags & DRM_MODE_FLAG_PIC_AR_MASK) {
        case DRM_MODE_FLAG_PIC_AR_4_3:
            out->picture_aspect_ratio = HDMI_PICTURE_ASPECT_4_3;
            break;
        case DRM_MODE_FLAG_PIC_AR_16_9:
            out->picture_aspect_ratio = HDMI_PICTURE_ASPECT_16_9;
            break;
        case DRM_MODE_FLAG_PIC_AR_64_27:
            out->picture_aspect_ratio = HDMI_PICTURE_ASPECT_64_27;
            break;
        case DRM_MODE_FLAG_PIC_AR_256_135:
            out->picture_aspect_ratio = HDMI_PICTURE_ASPECT_256_135;
            break;
        case DRM_MODE_FLAG_PIC_AR_NONE:
            out->picture_aspect_ratio = HDMI_PICTURE_ASPECT_NONE;
            break;
        default:
            return -EINVAL;
    }

    out->status = drm_mode_validate_driver(dev, out);
    if (out->status != MODE_OK) {
        return -EINVAL;
    }

    drm_mode_set_crtcinfo(out, CRTC_INTERLACE_HALVE_V);

    return 0;
}
EXPORT_SYMBOL_GPL(drm_mode_convert_umode);

/**
 * drm_mode_is_420_only - if a given videomode can be only supported in YCBCR420
 * output format
 *
 * @display: display under action
 * @mode: video mode to be tested.
 *
 * Returns:
 * true if the mode can be supported in YCBCR420 format
 * false if not.
 */
bool drm_mode_is_420_only(const struct drm_display_info *display, const struct drm_display_mode *mode)
{
    u8 vic = drm_match_cea_mode(mode);

    return test_bit(vic, display->hdmi.y420_vdb_modes);
}
EXPORT_SYMBOL(drm_mode_is_420_only);

/**
 * drm_mode_is_420_also - if a given videomode can be supported in YCBCR420
 * output format also (along with RGB/YCBCR444/422)
 *
 * @display: display under action.
 * @mode: video mode to be tested.
 *
 * Returns:
 * true if the mode can be support YCBCR420 format
 * false if not.
 */
bool drm_mode_is_420_also(const struct drm_display_info *display, const struct drm_display_mode *mode)
{
    u8 vic = drm_match_cea_mode(mode);

    return test_bit(vic, display->hdmi.y420_cmdb_modes);
}
EXPORT_SYMBOL(drm_mode_is_420_also);
/**
 * drm_mode_is_420 - if a given videomode can be supported in YCBCR420
 * output format
 *
 * @display: display under action.
 * @mode: video mode to be tested.
 *
 * Returns:
 * true if the mode can be supported in YCBCR420 format
 * false if not.
 */
bool drm_mode_is_420(const struct drm_display_info *display, const struct drm_display_mode *mode)
{
    return drm_mode_is_420_only(display, mode) || drm_mode_is_420_also(display, mode);
}
EXPORT_SYMBOL(drm_mode_is_420);
